CHEMISTRY COMMUNITY

JasmineReyes-2K

Hi,
To find the equilibrium constant you can substitute partial pressures, instead pure solids and liquids

JasmineReyes-2K

Hi,
To ensure the direction a reaction shifts, we'd look at the pressure levels. An increase in pressure would be a shift towards the side and vice versa

JasmineReyes-2K

Hi,
You would look at your given information and identify the corresponding units

JasmineReyes-2K

Hi,
You would look at your given information and identify the corresponding units

JasmineReyes-2K

Hi,
With the information given you can assume and convert units to find the ones you need.

JasmineReyes-2K

Hi,
expansion work is the work that is affected by the change of volume of gas in a system.

JasmineReyes-2K

Hi!,
Agreeing with others, there are times where you use the ideal gas law to estimate the relationship between P/V

JasmineReyes-2K

When systems are at equilibrium, they cannot work because they are at the same rate meaning that they will cancel each other out.

JasmineReyes-2K

hi!,
Yes!,When heat is added to water to vaporize and it changes to gas the actual temperature is not changing :)

JasmineReyes-2K

The difference between boiling point and vaporization is that boiling point is what is needed to begin the vaporization process. The higher the boiling point, the higher the vaporization.

JasmineReyes-2K

When delta H is negative,heat exits. When delta H is positive, heat enters

JasmineReyes-2K

hi!,
The relationship between entropy of the surroundings is that it will increase because heat itself is flowing into the surroundings.

JasmineReyes-2K

Hi!,
14=pH+pOH, we can use either or to find the other as long as they add up to 14
small Ka, strong acid
large Ka, weak acid

JasmineReyes-2K

Hi,
To assume a reaction has a dynamic equilibrium, we have to understand that I believe all the examples in this course are dynamic. But,dynamic equilibriums are interchangeable and constantly changing

JasmineReyes-2K

Hi!,
I would say yes because the temperature affects K itself which in return alters the type of process (endothermic or exothermic)

JasmineReyes-2K

Hi!,
In the exact problem from Achieve that you are talking about, you will use the delta temp (14.7) !

JasmineReyes-2K

Hi!,
To find temperature with this formula you would have to isolate T itself !

JasmineReyes-2K

Hi!,

It all depends on the units in the problem!

JasmineReyes-2K

Hi!,
An exothermic process releases heat, causing the temperature of the immediate surroundings to rise while an endothermic process absorbs heat and cools the surroundings.

JasmineReyes-2K

Hi!,
I think that since their values are so close to each other, we can interchange them and Lavelle also mentions this.

JasmineReyes-2K

Hi,
Enthalpy is determined whether the reaction is endo or exothermic, which will tell us if its positive or negative

JasmineReyes-2K

Hi!,
An open system does have a constant pressure while in a closed system, i agree with the commenters before that it will be stated

JasmineReyes-2K

Hi.
Im having trouble working out problems on my own, how do we always start a problem to calculate enthalpy ?

JasmineReyes-2K

Hi!,
Work done on a system is referring to an outside subject from its surroundings, doing the work. While work done by the system is in reference that the syste, is doing outside work to its surrounding subject

JasmineReyes-2K

Hi!,
there is actually no way to change an isolated system !

JasmineReyes-2K

How do certain bonds relate to enthalpy, in reference to q.6 from Achieve week 3/4

JasmineReyes-2K

Can someone explain to me how to find the enthalpy of a reaction ?

JasmineReyes-2K

Hi!,
Buffers are important because an equilibrium needs to be maintained

JasmineReyes-2K

Hi!,

a state property is calculated with the final and initial values, (final-initial)

JasmineReyes-2K

Hi!,

Melting is actually an endothermic process since it needs heat

JasmineReyes-2K

Hi!,
The way that I remember is exo=exit so I know that exothermic releases heat, and endothermic will take in

JasmineReyes-2K

Hi!,
This is because the heat energy is what is going through the phase change, not the heat

JasmineReyes-2K

Hi!,

This is usually already given but if not, you can assume based off your final answer having either H+ or -OH ions.

JasmineReyes-2K

When K is greater than Q , our forward reaction is favored, meaning there are more products than reactants

JasmineReyes-2K

Hi!,

A unique reaction rate is the increase or decrease in product concentration that is defined by our stoichiometric coefficient

JasmineReyes-2K

Hi!,

I think pKa is our -log of the equilibrium constant (K) while pH is the acidity of the whole equation which is -log of the Hydronium concentration

JasmineReyes-2K

Hi!,

Can someone tell me if I have to divide either 0.620 or 0.200 to find the initial concentration? I am not sure where to start

JasmineReyes-2K

Hi!,
I think generally we go based off if the value is less than 10^-4 !

JasmineReyes-2K

I was also confused about this concept, but it seems that K changes because our entire reaction is getting multiplied by a certain number that will change our constant

JasmineReyes-2K

K is our generic equilibrium constant while Ka is used as an acidity constant

JasmineReyes-2K

Hi,

I had this same question!

But I believe that we should always use our positive value over the negative value !

JasmineReyes-2K

Hi!,
X is negligible when the constant is smaller than 10^-4 or less than 5% of our initial concentration

JasmineReyes-2K

Hi!

Essentially a reaction is going to try to reach equilibrium so in this case, if products are increased, our K will be bigger. So we need to get K to become an equal ratio.

JasmineReyes-2K

Hi!,
I do think that it is because K is not something thats say given in a sense that way, we essentially have to find K based off other values which give the equilibrium.

JasmineReyes-2K

Hi!, You use an ICE table when solving for the concentration of molecules that you will use to find K.

JasmineReyes-2K

In the intro videos, Lavelle explained how K's value can determine whether the reactants or products are favored.

Can someone give me another brief summary?

JasmineReyes-2K

Can someone tell me what the difference between a Q and K constant is?

JasmineReyes-2K

Hi!,
The relationship between the two is they're proportional and linear. With the work function representing the least amount of energy required to eject electrons.

JasmineReyes-2K

Hi!,
I agree with others that the Rydberg equation might be the easiest approach (R[1/n1^2 - 1/n2^2]) by having the initial and final n

JasmineReyes-2K

Hi!

I see Autumn already gave you a detailed explanation but I would also suggest studying the Lymann and Balmer series, there are a lot of videos on YouTube that have helped me !

JasmineReyes-2K

Hi!,
Light essentially acts a wave through its diffraction patterns as seen as in the diffraction experiment where light can move in patters that simulate waves

JasmineReyes-2K

I genuinely did not fully know the answer but I went with what I did know. We do know that Gamma rays are strong, so I eliminated the choices that did not consider strong waves and from there you can get the answer

JasmineReyes-2K

I believe Lavelle has a solutions manual on the table of contents on the online book

JasmineReyes-2K

Hi!

You should first find the energy of each individual photon at their wavelength and find the total amount of energy in joules :)

JasmineReyes-2K

Can anyone tell me what I most definitely need to know well for the final? I am lost with content and what to study now

JasmineReyes-2K

We only use this equation for electromagnetic radiation and photons of light

JasmineReyes-2K

My TA told us to heavily focus on quantum numbers and coordination numbers !

JasmineReyes-2K

As far as I have grasped, it is a type of thermal electromagnetic radiation coming from a black body's environment.

JasmineReyes-2K

Hi everyone,

Lately I have been very confused on what is going on in lecture (with complete honesty), when Achieve is asking for the geometry of an atom, what do they mean?

JasmineReyes-2K

Hi!

As the others said before, you essentially can but you are actually just substituting rather than combining :)

JasmineReyes-2K

Hi!

Always try to use the lowest amount of sig figs based for your answers/values! This helps greatly when understanding your value and what your answer should be

JasmineReyes-2K

Can anyone give me guidance on how to start this question?

It is: "An organic compound that is distilled from wood has a molar mass of 32.04 g/mol. Its composition by mass is 37.5% carbon, 12.6% hydrogen, and 49.9% oxygen." , Should we find the molecular formula?

JasmineReyes-2K

Hi!,
Electron affinity is basically the amount of energy released when an electron is added to a neutral atom in its gaseous state. Also, it is key to know that the smaller the radius, the easier it will be to bind

JasmineReyes-2K

hi!,

It honestly depends on the equation but you can typically just use E=hv and c = λv to get your answer

JasmineReyes-2K

Hi!,

Always remember that electrons do have wave-like properties as shown through the split light model and we saw that it contains diffraction

JasmineReyes-2K

Is the final cumulative from midterm 1 and 2?

JasmineReyes-2K

Can someone tell me if the scores on CCLE for midterm 2 containing the partial credit scores as well? Also, should we expect a curve ?

JasmineReyes-2K

It should be ! I also very much hope that we can get partial credit as well

JasmineReyes-2K

Hi!

I think our grade automatically updates, but I don't believe they have talked about late deductions. I know some people who have turned in late assignments without penalty via Myucla where we can check our grade but I am not too sure.

JasmineReyes-2K

Try converting units when you are still dealing with distance, this honestly helped me so much :)

JasmineReyes-2K

Electrons don't move at the speed of light unfortunately

JasmineReyes-2K

Usually speed of light is constant as wavelength changes but I believe the frequency changes

JasmineReyes-2K

Hi!,
Make sure to use the Rydberg formula first !

JasmineReyes-2K

Hi can someone explain this question to me :

JasmineReyes-2K

Ive seen that our first three questions require us to draw structures, how are we supposed to do this on a laptop ?

JasmineReyes-2K

Hi!.
Does anyone know why my question 1 from achieve looks this way ? I am logged in via Mac and have refreshed several time :

JasmineReyes-2K

Typically the units are specifically asked for in the question so go based off that!

JasmineReyes-2K

You would first determine the energy of a single photon using Planck's constant and then will go into calculating the wavelength in meters into THEN calculating the energy of every single photon

JasmineReyes-2K

Q.15:

"You use an electron microscope in which the matter wave associated with the electron beam has a wavelength of 0.0449
nm. What is the kinetic energy of an electron in the beam, expressed in electron volts"

JasmineReyes-2K

From question #18 of Achieve, can anyone explain this equation and what we use it for ?

JasmineReyes-2K

Hi!

I am very confused on how to start question 8 of our homework, can anyone give me any advice?

"Calculate the wavelength, in nanometers, of the spectral line produced when an electron in a hydrogen atom undergoes the transition from the energy level n=6
to the level n=1."

JasmineReyes-2K

According to my TA, it would most likely be a mix of both and it would be very helpful to practice the book problems that he has outlined for us

JasmineReyes-2K

Can anyone give a quick rundown of how to use scientific notation? I feel I always get confused on how to use proper notation:

Please give examples!

JasmineReyes-2K

According to our equation sheet:,

eV to J is: 1 eV = 1.602x10^-19 J.

JasmineReyes-2K

I haven't been understanding much of what has been happening in lecture and do not know where to start here, can anyone offer any guidance? A liquid is exposed to infrared radiation with a wavelength of 9.44×10−4 cm. Assume that all the radiation is absorbed and converted to heat. How many photons a...

JasmineReyes-2K

Can someone please explain this week's question 3 to me, I am having trouble understanding why we multiply E to anything? Is this a formula or because of the question ? : Consider a single photon with a wavelength of lambda a frequency of v, and an energy of E What is the wavelength, frequency, and ...

JasmineReyes-2K

I also feel your confusion and I attended lecture. From my understanding, we use this formula when dealing with wavelengths and their distances

JasmineReyes-2K

When balancing the equations and we run into a situation where we have a fraction such as lecture, do we multiply by the nearest whole number or the denominator to cancel the fraction?

JasmineReyes-2K

Hi everyone!

Here is an acronym my TA David gave to use for sig figs!

JasmineReyes-2K

Will we have to be able to differentiate from constructive and destructive patterns?

If so, how do we differentiate ?

JasmineReyes-2K

Can anyone explain to me where Dr.Lavelle got 9.11 from in the denominator?

Time stamp from lecture video: 30:07

JasmineReyes-2K

Can someone explain what Dr.Lavelle meant by the Peak to peak saying for the wavelength?

JasmineReyes-2K

Heres an acronym that my TA David gave:
S. Sig figs decimal:
P. Present =
L. Leading zeros don't count
Decimals A. Absent
T. Trailing zeros don't count

EX.

0.0062 = 2 sig figs

JasmineReyes-2K

I try my best to calm my anxiety by drinking tea but I believe your mentality going into the exam is what matters MOST. Go into the exam saying that you will do well!, tell yourself that you are intelligent and worthy to be there !

JasmineReyes-2K

I always like to think of the smallest value being it, either unit !

JasmineReyes-2K

Hi!,

I believe we all have different values ? Maybe post a screenshot so we can see your values?

JasmineReyes-2K

Pasta!!!

Search found 97 matches